Liver abscesses.

Clinical suspicion of a liver abscess mandates an investigation of the liver for evidence of a liver abscess by radionuclide, ultrasound, or CT scan. Amebic abscesses have a lower mortality rate than pyogenic abscesses. Amebic and pyogenic abscesses can be distinguished on the basis of epidemiologic, clinical, and laboratory studies. The definitive studies for identifying amebic liver abscesses are hemagglutinin or gel diffusion studies. Amebic abscess of the liver may be complicated by extension to the lung, with pulmonary complications. Patients suspected to have amebic abscesses require metronidazole. Emetine or chloroquine may be added if there is no response or if the abscess recurs. Unless there is a failure of the amebic abscess to resolve or secondary infection occurs, there is seldom a need to aspirate or drain these abscesses. Pyogenic abscesses should be treated with broad-spectrum antibiotics to cover gram-negative aerobes and anaerobic organisms. All pyogenic abscesses larger than 1.5 cm in diameter should be aspirated, and the aspirate should be Gram stained and cultured. Percutaneous or surgical drainage should then be performed. Operative intervention is required in those patients with intra-abdominal pyogenic infections that are seeding the liver abscess. The marked reduction in the mortality rate of pyogenic liver abscess witnessed in this decade is multifaceted and attributable in part to earlier diagnosis, permitting definitive treatment in a timely fashion, as well as to improved intensive unit care, antibiotic management, and operative technique.